Breakdown of Die Eishalle ist alt, darum hat die Temperatur aufwendig reguliert werden müssen.
sein
to be
haben
to have
alt
old
müssen
to have to, must
Questions & Answers about Die Eishalle ist alt, darum hat die Temperatur aufwendig reguliert werden müssen.
Why are there three verbs at the end of the sentence (reguliert werden müssen)?
This is the passive voice in the present perfect tense (Perfekt) combined with a modal verb. When a modal verb is used in the perfect tense alongside another verb, it takes its infinitive form instead of its past participle. This is known as the double infinitive rule. The structure at the end of the clause is the past participle of the main verb (reguliert) + the passive auxiliary (werden) + the modal infinitive (müssen).
Shouldn't the past participle of werden be worden in the passive voice?
Normally, yes! In a standard perfect passive sentence without a modal verb, you use worden (for example: Die Temperatur ist reguliert worden). However, when you add a modal verb into the mix, the passive auxiliary reverts to its standard infinitive form (werden).
Why does hat come right after darum instead of being pushed to the end of the sentence?
The word darum (therefore / that is why) is an adverb, not a subordinating conjunction. Because it occupies position 1 in this main clause, the conjugated verb (hat) must strictly follow the V2 rule and take position 2. The subject (die Temperatur) then follows in position 3.
How does the word aufwendig translate here?